1. Field of Invention
The present invention relates to a coaxial cable end connector. More particularly to a coaxial cable end connector for being connected with an end of a coaxial cable having a small diameter.
2. Description of Related Art
Antennas disposed in high-frequency wireless electric devices are Generally installed outside printed circuit boards for lowering the influence of high frequency electric components disposed on printed circuit boards on high-frequency wireless signals emitted from the antenna. Therefore radio frequency properties of the antennas can be prevented from being unstable due to the operation of the electric components disposed on printed circuit boards. The communication of electrical signals between the antennas and printed circuit boards generally relies on the coaxial cable used as a signal transmission medium. In the limited space of the electric devices, an outer diameter of the coaxial cable and volume of the coaxial cable end connector compatible to printed circuit board are required to be as miniaturized as possible.
As shown in the figures, among the conventional coaxial cable connectors for being connected with an end of an axial cable having a small diameter, a design of a typical coaxial cable connector for being connected with an end of an axial cable having a small diameter is disclosed in U.S. Pat. No. 6,508,668. The conventional coaxial cable connector includes an insulating housing A1, a signal terminal A2, and a shielding housing A3. The insulating housing A1 has a first surface A11 and a second surface A12 opposite to the first surface A11. The first surface A11 of the insulating housing A1 faces a pair of connectors (not shown in the figure). The central region of the second surface A12 of the insulating housing A1 includes a hollow hole A121, a terminal cavity A122, and an insulating plate A123. The hollow hole A121 of the insulating housing A1 is formed penetrating the first surface A11 and the second surface A12. The terminal cavity A122 of the insulating housing A1 communicates with the hollow hole A121. The signal terminal A2 is disposed in the terminal cavity A122 of the second surface A12 of the insulating housing A1. The signal terminal A2 includes a flat portion A21, two opposite end walls A22, and a pair of contacting arms A23, in which the end walls A22 are formed respectively by bending the opposite ends of the signal terminal A2 in a direction toward a backside of the first surface A11, and the contacting arms A23 are respectively disposed on edges of the signal terminal A2 without the end walls in a direction toward the first surface A11 of the insulating housing A1. The two end walls A22 of the signal terminal A2 have a concave A221 for accommodating an internal conductive wire B1 of a coaxial cable B, so that an end of the internal conductive wire B1 of the coaxial cable B can be soldered with the flat portion A21 of the signal terminal A2. The contacting arms A23 of the signal terminal A2 are used for communicating electrical signals with a corresponding connector (not shown). The shielding housing A3 has an circular portion A31 and a cover A32, in which the cover A32 of the shielding housing A3 surrounds the outer surface of the insulating housing A1, and the cover A32 of shielding housing A3 presses the insulating plate A123 of the insulating housing A1 to be flattened between the cover A32 of the shielding housing A3 and the signal terminal A2. A set of front fasteners A321 and a set of back fasteners A322 are extended from the cover A32 of the shielding housing A3, in which the front fasteners A321 and the back fasteners A322 fasten a metallic shield 63 (metal wire mesh) and an external insulating layer B4 of the coaxial cable B respectively.
The general coaxial cable B suitable for the prior art skill is a four-layer structure, including the internal conductive wire B1, an internal insulating layer B2, the metallic shield B3, and the external insulating layer B4 arranged from a center to an external surface of the coaxial cable B sequentially. Since the end of the internal conductive wire B1 of the coaxial cable B is soldered with the flat portion A21 of the signal terminal A2 of the connector, and the metallic shield B3 and the external insulating layer B4 of the coaxial cable B are fastened respectively by the shielding housing A3 of the connector, the connector is combined with the end of the coaxial cable B firmly.
Since the coaxial cable end connector is soldered with the end of the coaxial cable B, and the coaxial cable end connector is suitable for the coaxial cable B of a single internal conductive wire, the internal conductive wire B1 of the coaxial cable B is one single inseparable conductive wire. For another coaxial cable B having internal conductive wires, the internal conductive wires are separable, so that it is difficult for a production line to neatly solder the respective internal conductive wires each having a small diameter with the fiat portion A21 of the signal terminal A2. The prior art skill is to solder the internal conductive wire B1 of the coaxial cable B with the flat portion A21 of the signal terminal A2. However, the scattered internal conductive wires each having a small diameter are difficult to be soldered, and the multi-core conductive wires of the respective coaxial cables of various coaxial cable end connectors generally have great differences for tin-wetting, resulting in the inconsistent electrical characteristics of the coaxial cable end connectors after soldering, and thus the conventional skills have to be improved.